We propose a series of experiments aimed to develop rapid detection of two most common PML-RARalpha fusion mRNAs from mammalian cells using MEMS-based electrochemical sensor array. The ultimate goal of the studies is the development of an inexpensive, user-friendly system capable of diagnosing 90 percent of APL cases in less than one hour. Such a system would facilitate initiation of ATRA within hours, instead of days, of initial presentation, and thereby reduce the risk of life- threatening hemorrhage. Once the system is completed the greatest benefits of this integrated system will be higher complete remission rates, and more importantly, improved overall survival of patients with APL due to earlier diagnosis. Furthermore, this novel technology promises to be of growing potential use to the field of oncology, where the molecular alterations which drive malignant diseases processes are continuing to be characterized. Perhaps the most well-studied molecular alteration associated with human malignancy is the Philadelphia chromosome found in the leukemic cells of >95% of patients with chronic myelogenous leukemia (CML), which results in the fusion of BCR and ABL genes. The detection system we aim to develop here is expected to be made amenable to the rapid diagnosis of CML and perhaps other malignancies as well. Molecular diagnosis of alterations in oncogene or tumor suppressor gene expression, translocations, and others predisposing genetic alterations will increasingly be used for cancer detection and choice of therapeutic options. The speed, versatility, portability, ease of use and cost of the handheld MEMS- 0based electrochemical array detection are significant advantages over current molecular technologies. The analytical validity of a prototype PML/RARalpha sensor array will be shown through milestones in Phase I. PROPOSED COMMERCIAL APPLICATIONS: GeneFluidics' Life Science/Electrochemistry Laboratory is located in Torrance, CA, a business/industrial area of Los Angeles, CA. This location is 20 minutes from UCLA where Dr. Irvin Chen and Dr. Neil Shah have their office. Our laboratory occupies 1,000 square feet. For research and development purposes, there are 4 desktop computers, 3 laptop computers and complete internet access and network connection. Our laboratory has a section for machining and electronics prototyping. An isolation room is built for "dirty" machining and the room is pressurized so it won't contaminate the experiment setup outside the isolation room.